Ukraine itself is a complex mesh of ethnicities, languages, cultures and allegiances. As a result, the conflict itself has is just as complex. Not only are both sides divided amongst themselves about their goals and tactics, but each accuses the other of being a puppet for foreign backers and claims foreign fighters are involved.

Who is fighting in Ukraine? What do they want?

This may seem like the simplest question, but it is in fact one of the most complex, and goes to the heart of why there is a conflict in the first place.

There are, broadly speaking, two sides: those who want to free Ukraine from Russian influence and those who prefer to maintain a close cultural and political relationship with Russia.

Within those two sides, there are also several factions. The side that rejects Russia includes those who want to forge closer ties with Europe, as well as more nationalist elements that are interested more in maintaining Ukraine’s independence and defending its sovereignty. Even within that nationalist wing, there are more radical elements that have sought to expunge Russian influences and many, like the group Right Sector, who are willing to take up arms to do so.

Among the pro-Russian side are ethnic Russians in southeastern Ukraine. They speak Russian at home and many have family across the border. They fear the new anti-Russian government in Kiev is out to get them and believe ultra-nationalist fascists and neo-Nazis are taking over the country. There appears to be disagreement among them about the end goal. Some of them want to form a separate country. Others want to join Russia. Another factions wants to remain part of Ukraine but want more autonomy and power for their region. Still others just fear they are under attack. They also seem to disagree about where to draw the boundary for their new territory.

The pro-Russian side, as well as the Russian government, alleges that militants from Right Sector are fighting alongside the Ukrainian army. The Russian government has also accused foreign English-speaking mercenaries of taking part in attacks.

The Kiev government and its allies in the West, however, accuse Russia of sending special forces and intelligence operatives into the east to stir up trouble, arm, fund and train the separatists. They claim Russian operatives have led the charge to take over towns and government buildings, followed by locals who then occupy them. They also claim that so-called “protest tourists,” including Cossacks, crossed the border from Russia to participate.

What caused the recent escalation?

Towns like Slovyansk in eastern Ukraine were taken over by pro-Russian separatists in recent weeks. In other major cities the armed separatists took over government buildings. After several false starts, the Ukrainian military has begun a military offensive to clear them out. Russia denounced this as the Kiev government using force against its own people .

In Odessa, observers say the clashes on Friday that led to the horrific fire that killed about 40 people seemed to come out of nowhere. The city had been relatively quiet throughout the uprising in Kiev, the annexation of Crimea, and the unrest in the east. The circumstances are still murky, but what’s clear is that Right Sector groups clashed with a pro-Russian group that attacked a procession. Exactly who started the fire remains unclear. U.S. officials have privately alleged that Russia had stepped up provocations in the city in recent days.

Odessa is now a city on edge and fears are high that clashes could break out again.

Will Russia invade?

This is the million dollar question. The Kremlin insists it has no plans to do so, but authorities in Kiev, Europe, and Washington do not trust them. They point out that Russia’s assurances about its intentions in Crimea proved to be false. They also note that Russia still has tens of thousands of troops waiting along the border with Ukraine. They are ostensibly there for training exercises, but the U.S. officials say they are poised to enter Ukraine if the order is given.

How did this start?

The uprising began in late November, when then-President Viktor Yanukovich rejected an association agreement with the European Union in favor of a deal with Russia. He said it provided his country better access to badly needed funds, as Ukraine’s economy is teetering on the brink of default. Yet many saw his move as a rejection of a European future in favor of one in the Kremlin’s hands. Street protests began in central Kiev’s Independence Square, known as the Maidan. At times the protests swelled to over a hundred thousand people.

Finally, in February, Yanukovich’s forces tried to clear the square and clashes broke out. Eventually, after a peace deal was signed, Yanukovich fled and the riot police melted away. The new pro-Western government took over and scheduled elections for May 25.

Will the U.S. intervene?

President Obama has ruled out the use of force in Ukraine. Instead, he is relying on a combination of international sanctions and pressure on Russian President Vladimir Putin to stop what the United States says is Russia’s continued meddling and provocation in Ukraine.

The U.S. has so far enacted three rounds of sanctions. The last two rounds have targeted members of President Putin’s inner circle. The White House warned that it could slap even harsher sanctions, potentially targeting Russia’s lucrative energy and mining sectors, if Russian troops cross the border.

So far, Washington’s allies in Europe have issued their own sanctions, but have been reluctant to go along with such tough measures since they rely on Russia for a significant portion of their energy imports and have larger trading relationships with Russia than the United States does.